There are spectacular looking pools with overflow systems in which the water rises to the same level as the border channelling it over the edge of the pool into the recirculation system. Infinity Edge Pools that offer breathtaking views. Other possibilities include runoff systems with various types of ridges around the edges of the pool or runoff systems that are out of sight under the water. Owners can also decide which type of water they want in their pool; chlorinated or salt water.